1. Field of the Invention
The present invention relates in general to an air suspension bed. More particularly, but not by way of limitation, the present invention relates to an air suspension platform for bedding useful in moving vehicles such as, for example, trucks or like vehicles.
2. Description of the Related Art
In tractor-trailer trucks for hauling loads long distances, it is common practice to provide a sleeping compartment in the truck. Where the truck is being driven by a single driver, no particular problem is encountered since, in order to obtain the desired rest for the driver, the truck is necessarily stationary when the driver is sleeping or resting. However, in order to substantially increase the number of hours of operation of the truck to meet delivery schedules, two drivers are frequently assigned to a single vehicle, with one of the drivers resting and/or sleeping while the other is driving. As will be appreciated, attempting to sleep under driving conditions can be difficult, particularly when rough road conditions are encountered. The trucks experience continual vibrations, including vertical bouncing and pitch movements of a magnitude which would make it almost impossible to sleep on an ordinary non-suspended mattress. In a cab-over-engine truck or tractor unit where the cab extends well above the pitch center of the chassis, fore and aft movements of substantial magnitude occur, as well as side-to-side motion, which will all be amplified tremendously at the height of the bed above the road.
Attempts have been made in the past to provide supplemental underlying supporting means for sleeping mattresses or the like in order to provide a more comfortable supporting surface and one which is relatively more immune to rough road conditions. However, these prior art supplementary supporting systems have been less than completely satisfactory for a number of reasons, including the lack of simple and reliable cushioning means which will compensate passengers of various body weights. Moreover, the problems are compounded because of economics and because of the very limited space available at the sleeping compartment in the truck.
In the known prior art numerous implementations of suspensions systems have been taught. For example, U.S. Pat. No. 3,371,359 discloses a mattress suspension system comprising a lower support frame and an upper support frame. A pair of air suspension units are operatively connected between the lower and upper support frames. The air suspension units are simultaneously actuated and the upper support frame is automatically leveled to a neutral position regardless of the weight of the individual.
U.S. Pat. No. 3,760,436 discloses a suspension system which includes a mattress support box which is mounted for fore and aft movement relative to a frame structure by pivoted link members. Isolation of the mattress support box from vertical vibratory motions is provided by a scissors linkage. Vertical movement of the scissors linkage is controlled and restrained by a gas spring assembly operatively connected to one end of a link member.
U.S. Pat. No. 4,144,601 discloses an air ride sleeper comprising a frame which holds a mattress. At each end of the frame is a scissors-type vertical support positioned between the frame and a slide together with air cushions to provide vertical cushioning of the frame.
U.S. Pat. No. 4,196,483 discloses a portable mattress support which comprises a lower frame and an upper frame capable of being moved with respect to the lower frame by a scissor-like arrangement of intersecting levers located at each end of the support. A fluid cylinder is positioned at each end of the support to force the frames apart.